1. Field of the Invention
The present invention relates to a toner container and a developer replenishing device to be detachably installed in an image forming apparatus in order to replenish toner to a developing device built-in the image forming apparatus such as a copying machine, a printer, a facsimile machine, and the like, and an image forming apparatus.
2. Description of the Related Art
A toner container disclosed in Japanese Unexamined Patent Publication (Kokai) No. 2003-280344 is known as prior art. This toner container is to be detachably installed in a developing device in order to replenish the developing device built-in an apparatus main body of an image forming apparatus with toner. More specifically, the toner container replenishes the developing device with toner when an amount of toner within the developing device becomes less than the preliminary set amount.
Such a toner container includes a box-like container to be charged with toner, a toner conveyance screw provided at a bottom of this container in order to replenish the developing device with toner by thrusting the toner within the container, a driving force transmitting portion for transmitting a driving force from a driving motor to the toner conveyance screw; and a cylindrical shutter member rotationally provided at an appropriate location of the container conforming to an outer peripheral surface of the toner conveyance screw. The shutter member is rotatable around the cylinder axis between a closed position where the shutter is closed and an open position where the shutter is open.
When the toner container is slidably installed to the developing device, the rotational shutter member rotates from the closed position to the open position due to an interference with some member of the developing device to allow a passage between an inside of the toner container and an inside of the developing device. Accordingly, the developing device is replenished with toner from the container by a driving of the toner conveyance screw through a refill opening of the container.
To the contrary, when the toner is removed from the developing device in order to exchange an old one for an new one, the rotational shutter member rotates in a backward direction (namely, from the open position to the closed position) to close the shutter member by release of the rotational shutter member from the interference (i.e., an interference opposite to the former interference is applied), thereby preventing the residual toner within the container from leaking to the outside.
On the other hand, the toner container disclosed in Japanese Unexamined Patent Publication No. 2003-280344 is installed into the developing device in such a manner that the toner container is slidably installed onto a top surface of the developing device which is built-in the apparatus main body of the image forming apparatus. Therefore, a bottom surface of the container is made into a flat surface so as to allow the toner container to slide on the developing device smoothly. In other words, it is not necessary to provide a supporting leg for supporting the container on the bottom surface of the container; on the contrary, an inconvenience may occur in sliding the toner container if a leg exists on the bottom surface of the container. As such, the leg is not provided.
To the contrary, it is not required to consider the above described sliding movement in the image forming apparatus of a type in which the toner container is attached to and detached from the apparatus main body from a top thereof, such that flexibility in designing the bottom surface of the container increases. Therefore, considering an agitating ability or the like of an agitator, there are many cases where a shape of the bottom surface of the container is made into an arc-shape in cross sectional view. In this case, if the bottom surface is made into the arc-shape, stability of the container when it is placed on a flat surface becomes poor, resulting in inconvenience during exchange of the toner container. Accordingly, a plurality of supporting legs is generally provided on the bottom surface of the container.
However, if only the supporting legs are provided on the container, the number of parts increases and thereby invites an increase of cost.